ever since i purchased the 20th several years ago, the random "Lamp out" yellow lense would illuminate randomly but then go away.
a week ago it came on and didnt extinguish like it usually had done in the past.
to save a lengthy thread about what all the unbelievable additional symptoms are happening, here is what i have isolated down as what i feel could be the root abnormality.
1
with no keys in, if i simply go sit in the drivers seat and depress the brake, the front outter marker (yellow) lamps come & inner headlamps come on along with the normal rear lamps.
2
additionally what i have noticed is when i am in a left turn mode, the illumination on the right side bulbs strobe in sync with the left lamps.
3 my chime module is chiming very low now much lower than it usually does.
Item 1 i believe is causing all the other odd things happening id rather not list unless someone is interested, i just think they are all rabbit holes that lead nowhere when i see one fault that could correct the situaton.
I am going to stew through my EVTM but wanted someone else to see if they could find a common denominator as well.
By "inner headlight" I am guessing you mean the parking light.
Page 92
No ground on the four brake/parking lights.
When you step on the brake the current feeds back through the parking light, through fuse 15 and through the front parking lights to ground.
the lamps on either side of the grille, they come on along with the left/right front turn bulbs when i step on the brakes.
for this issue, i was starting to think the multifunction switch is hosed up on the inside somehow especially since its a **Huge** problem when i activate the left turn signal.
humm,, im "almost" confussed,, second attemp on page92 of the 87evtm tomorrow. page 92 is "without" lamp out warning but the gray box says "with lamp out warning".
i was looking at page 95.
basically i know that no bulbs should ever come on up front when i step on the brake pedal.
Check the tail light ground connection G1201. It's probably rusted out. G1201 is located on the trunk lid latch brace.
Yes there is some mislabeling. Page 92 has the resistance wires for the lamp-out feature. Page 89 is the without lamp-out feature diagram.
will do.
Does this help?
From what you describe you have a ground issue i would think. Remember the multi function switch also controls the stop lights when you are making a turn they double as signals. What i usually do is test the lamps with a test light to ground and operate the lamps with the issues. Touch the side of the lamp casing with your test light probe. If it comes on dim or flashes ETC you have a bad ground easily repaired at the source. Sounds like you are back feeding looking for a ground. Easy to trouble shoot with a test lamp. You know the old fashioned one not a LED or electronic one. Back test the grounds and you will find it. I THINK???
I have dug in pretty deep, getting nowhere but the problem is not critical. I have a VW in the garage under daily TLC for 2 months of afternoons now which is taking all my time.
so... one of the thing i mentioned earlier i said i would not get into may be important...a symptom so to speak.
~with headlamps off, if i press on the brake pedal my marker lamps on either side of the grill light up *but* in additon my instrumentation relay de-energizes so my dash goes dead.
~with headlamps off, with *no* brake applied, if i do just a turn signal to the left, the flasher and cluster indicator strobe & clicks very very quickly
~with my headlamp switch moved to the marker or headlamp lamp position, if i depress the brake, the instrumentation relay is not effected so the cluster stays on.
~with my headlamps on, with *no* brake applied, if i do just a turn signal to the left, the flasher and cluster indicator strobe & clicks very very quickly
I think my car is telling me there is a "Lamp out" for a good reason.(car does not have system sentry, just the one bulb on the lower left of the cluster). It appears i have the left side of my instrument cluster going dim or it goes completely dark intermittantly. If i have a bulb out in the dash, this might be the cause,, just speculating although no diagrams indicate the "full" digital cluster is observing "all" lamps. The diagrams indicate that the rear lamps are only monitored but all rear lamps are good.
i have not performed the missing ground test yet, no excuses here, just letting you know time has not been on my side.
Personally, my first step was to do a safe back out of my relay mod for IGN & ACCY slave relays and also back out of the headlamp mod and position all the wiring as original to make sure my mod is not "finally" the cause of the problem. It is a reality i have to consider.
the only lamps that are actually out in my "full digital cluster" are the bulbs that are lighting up my left side of my dash.. they seem to have progressed from intermittant to partially lite up in the past few days. Im betting that if i repair this part, perhaps the issue will be solved but again, the diagrams dont say that.
Understood,
I am mostly having trouble understanding where in the circuit to start because i cant seem to layout where the brake switch can feed the lamps that are coming on ***UP FRONT***.
my first gut instinct was telling me i have a faulty multifunction switch with an internal failure.
i feel like a troll now though,, i havent even checked for a blown fuse... need to do that today.
Time to DIG IN JAY!!!
I guess the diagram I posted in post #7 is not very clear.
The brake light current goes through the brake element of the dual element bulb, then through the parking light element of the same bulb. From there it goes through the elements of the front parking light bulbs to ground.
your diagram is clear, i knew where you were going earlier. Its just that under this condition as you have it sketched out, both elements should be on during the fault, this is not the case. also the condition is only during a left hand turn.
Just one or both tail light bulbs on the left side not grounded would cause the brakes to turn on all the front parking lights.
Also it would cause the left turn to flash all the front parking lights.
You are right, it would cause both elements in the ungrounded bulb or bulbs to light up.
I thought you said in your original post that stepping on the brake also caused the problem to show up.
If you would pull the left side tail light bulbs out and and still have the problem, that would let me stop thinking about them and go on to something else.
as of now the left side of my instrument cluster illumination is completly out... dark except for my beng able to barely make out the data displayed for fuel, temp ect.
***********since the left side of the instrument cluster illumination finally went totally dark, all symptoms disappeared with this malfunction and the only thing that still remains is the left side of my cluster illumnation is dark~~!!!!!!!! what a problem here eh?
Im thinking ill just replace the cluster illumination bulbs and montior it. talk aobut a jacked up problem!
yes, stepping on the brake caused my front inside only lamps to come on with no headlamps picked which is how i concluded this must be the root fault, and finding out how this is possible without illuminating other bulbs is kicking my butt. car 100% stock except for Ign/Accy slave relays and a headlamp mod using the auto lamp relays to work front / marker lights.
-causes my rear lamps to light up like normal
-causes my front lamps on either side of the grille to come on steady
-causes my instrument cluster illumination to go dark
steping on the brake with marker and / or headlamps selected:
-causes my rear lamps to light up like normal
-causes my front lamps on either side of the grille to come on steady
-instrumentation cluster illumination stays on as normal.
-during L turn condition with no brake, with no lights, the turn flasher makes a quick irratic fast switching noise, left rear lamps flash but right lamps appear strobe a little, instrumentation cluster remains on, front inside lamps remain off
-during L turn condition with brake, with no lights picked, the turn flasher makes a quick irratic fast switching noise, left rear lamps flash but right lamps appear to strobe a little, instrumentation cluster will switch on and off in opposite reacton to the left turn signal arrow shown on the dash, front inside lamps will come on and flash.
-during L turn condition with no brake, with lights, the turn flasher makes a quick irratic fast switching noise, left rear lamps flash but right lamps appear strobe a little, instrumentation cluster remains on, front inside lamps remain off
-during L turn condition with brake, with lights picked, the turn flasher makes a quick irratic fast switching noise, left rear lamps flash but right lamps appear to strobe a little, instrumentation cluster remains on, front inside lights do not flash but remain on.
Have you made certain that all the rear bulbs are correct? I remember a couple occasions where I had a similar concern on other vehicles, and found a 3156 in place of a 3157 and another where I found somebody had literally jammed an 1156 in place of an 1157 (hard to do). Without crawling through the EVTM, that's all I've got.
just curious as to how a mistake on a 3156 and 3157 would cause a back circuit ??????
1156 and and 1157 YES !!!
You'll have to forgive me, Tom, but it's been over 12 years since the last time I dealt with an incorrect bulb backfeed, my memory is a little foggy that far back. People don't seem to be that inept these days. One was an early 90's Crown Vic, and the other was a Saturn L. Back in 00 or 01.
the rear has never had any bulbs changed.
i did purchase about a half dozen 1156 & 57 bulbs at autozone for troubleshooting plus spares.
I did swap out the 4 rear turn 1157's with no change.
my sockets are round on the rear, not flat blade type. I did notice (for the first time ever!!) that my rear sockets are hard plastic on the 20th, not those soft rubbery ones like on my 87LS. on those soft plastic sockets, over time, you can actually put an 1157 in backwards if your not carefu..... that will cause you some problems for sure. ITs almost like some improvement was made to tail lamp sockets during 87 sometime.
i still have no clue how stepping on the brake can cause the instrument cluster relay to power off and ultimatly power on the inner front lamps on either side of the grille.
i spent a couple hours looking at the shop manual digging into the full digital cluster wiring in various chapters and its my belief this harness is unique to the point that the wiring diagrams are not really exact. this isnt the first time ive ran across not being completly clear on something having to do with a full digital star wars cluster.
The problem is, stepping on the brake is "energizing" the instrument cluster relay. This switches control of the LCD brightness to the dimmer pot in the headlight switch. Since the HL switch is off there is no power to the dimmer pot. The LCD's go off.
When the relay is de-energized, the LCD's are on full bright.
Stepping on the brake is turning on exterior lights, parking lights, running lights or whatever you want to call them.
The exterior lights circuit energizes the instrument cluster illumination relay.
as of my left side instrument cluster going dark that i posted earlier, late march 2013, i finally felt comfortable pullling the cluster to replace bulbs.
also replaced the radio bulb,
no further symptoms to date with this odd problem.
root cause here was apperantly cluster related and my car being full digital cluster, i still have no idea how or why this happened.
I simply had to wait for whatever it was to finish breaking itself.
im my opinion , this issue is gone.
I have always had uneven illumination, not it looks just like the sales brousure , nice and bright and all purdy!!!
softtouch~ also my old problem is gone with AM stations getting alternator noise. I have this adaptor on my rear window to hold a sort antenna like back in the day when all these cars had a car booster for thier cell phones. well i guess the shop that did the work intercepted some how my car antenna into a "Y" such that the adaptor was plugged into my radio. That coupled with the fact the radio was not cliped into the horizontal mount to get a good chassis ground helped as well. I deleted the extra antenna connection and now i get nice clean AM band as well as much more FM stations than before.
Glad you fixed it, but dude, who still listens to AM radio?
well,, its how i stay informed,, so im not one of the "low information voters"
FM offers very little talk radio in my region unless im on a road trip which is fairly often
If I wanted to hear endless talking on the radio, I'd go home and listen to my wife. She doesn't EVER stop talking, I'm still trying to figure out when she has time to breathe.
yes,, but,
new bulbs curing my original problem?
crazy isnt it?
without a proper detailed diagram of the cluster, I couldn't say, however, I suspect a backfeed of some sort, maybe on the ground side. It would be something unrelated that only surfaced because of the cluster lights. That's my best guess.